MPs back creation of human-animal embryos

British scientists will be allowed to research devastating diseases such as Alzheimer's and Parkinson's using human-animal embryos, after the House of Commons rejected a ban yesterday.

An amendment to the Human Fertilisation and Embryology Bill that would have outlawed the creation of “human admixed embryos” for medical research was defeated in a free vote by a majority of 160, preserving what Gordon Brown regarded as a central element of the legislation.

The Government is braced for defeat today, however, on a separate clause that would scrap the requirement that fertility clinics consider a child's need for a father before treating patients. MPs will also consider amendments tonight that would cut the legal limit for abortion from 24 weeks to 22 or 20 weeks.

A second amendment, which would have banned the creation of “true hybrids” made by fertilising an animal egg with human sperm, or vice-versa, was also defeated yesterday by a majority of 63. Another free vote last night was expected to approve the use of embryo-screening to create “saviour siblings” suitable to donate umbilical cord blood to sick children.

Edward Leigh, Conservative MP for Gainsborough, moving the amendment to ban all admixed embryos, said that mingling animal and human DNA crossed an “ultimate boundary”. He said that exaggerated claims were giving patients false hope and that the dangers of the research were unknown. “In many ways we are like children playing with landmines without any concept of the dangers of the technology we are handling,” he said.

Mark Simmonds, a Shadow Health Minister, who moved the amendment to ban “true hybrids”, said that there was no compelling evidence of their research usefulness.

Evan Harris, the Liberal Democrat MP for Oxford West, challenged those who accepted admixed embryos in principle but rejected “true hybrids” to explain the ethical difference between an embryo that was 99 per cent human and one that was 50 per cent human.

Dawn Primarolo, the Health Minister, agreed: “Once we go down that road it seems illogical to oppose a particular mix.” Ms Primarolo said that the shortage of human eggs was the biggest barrier to embryonic stem cell research. The Minister admitted that the Bill was not a promise that cures for diseases could be found. “It is an aspiration that it may,” she said.

The amendment to ban all admixed embryos was defeated by 336 votes to 176. The prohibition on true hybrids was defeated by 286 votes to 223.

The main kinds of admixed embryo permitted by the Bill are “cytoplasmic hybrids” or “cybrids”, which are made by moving a human nucleus into an empty animal egg. These are genetically 99.9 per cent human. As well as true hybrids, it also allows chimeras that combine human and animal cells, and transgenic human embryos that include a little animal DNA.

The most immediate implication of the Commons vote will be to allow teams at the University of Newcastle upon Tyne and King's College London, which already hold licences to create cybrids, to continue their research. Though they were cleared to start these experiments by the Human Fertilisation and Embryology Authority in January, their licences would have been rescinded had MPs voted for a ban.

Cybrids could carry the DNA of patients with genetic conditions to create stem-cell models of these diseases for studying their progress and testing new treatments. Human eggs could be used but are in short supply because of risk to donor women.

It is legal to culture admixed embryos up to 14 days and illegal to transfer them to a human or animal womb.

The decision will also encourage a third team, which plans to use admixed embryos to study motor neuron disease, to apply for a licence. The group, led by Professor Chris Shaw, of the Institute of Psychiatry in London, had been waiting for the vote.

Professor Shaw said: “It will allow us to forge ahead on all fronts in our attempts to understand and develop therapies for a huge range of currently incurable diseases. Cures may be some years off, but this vote does mean we can use hybrid embryos, in addition to adult stem cells, in our search to understand what causes Alzheimer's, Parkinson's and motor neuron disease.”

Professor Robin Lovell-Badge, of the National Institute for Medical Research in London, said the vote would aid understanding of normal embryonic development and of genetic disease: “This understanding will ultimately give us the best chance of developing therapies for these diseases, for infertility and for a range of other medical conditions”.

RESOURCE/SOURCE:  www.timesonline.co.uk on May 20, 2008